P3492Carvedilol and its analogue VK-II-86 attenuate stretch-induced manifestations of mechanoelectric feedback

Background

Mechanical stretch modifies Ca2+ handling and myocardial electrophysiology, favoring arrhythmogenesis. The store-overload-induced Ca2+ release (SOICR) through the ryanodine receptor (RyR2) seems to be implicated in this deleterious effect. Carvedilol and its analogue VK-II-86 (which does not have significant beta-blocking effects) suppress SOCIR by directly reducing the open duration of the cardiac RyR2, and could modulate calcium-related changes produced by myocardial stretch.

Purpose

The aim of this study was to investigate, by the ventricular fibrillation (VF) spectral analysis, whether carvedilol and VK-II-86 prevents stretch-induced arrhythmogenic effects.

Methods

The VF modifications induced by acute stretch were studied in Langendorff-perfused rabbit hearts using epicardial multiple electrodes under control conditions (n=10), during carvedilol infusion (0.1 and 1 μM) (n=10) and during VK-II-86 infusion (0.1 and 1 μM) (n=10). Spectral techniques were used to establish the baseline and stretch characteristics in the three series above mentioned: VF dominant frequency (DF) and VF spectral concentration (SpC) were determined. A two-factor ANOVA test was used and significance was reached when p<0.05.

Results

Myocardial stretch significantly increased DF with respect to pre-stretch values in control conditions (13.3±1.2 vs. 16.1±3.0 Hz, p<0.05) and during the perfusion of 0.1μM carvedilol (11.6±1.5 vs. 13.6±2.9 Hz, p<0.05) and 0.1μM VK-II-86 (13.2±2.2 vs. 16.2±4.1 Hz, p<0.05). However, the maximum concentration of both drugs (1μM) abolished this stretch-induced VF acceleration (carvedilol: 6.9±2.2 vs. 7.3±2.6 Hz, ns; VK-II-86: 7.0±1.4 vs. 7.1±0.6 Hz, ns). The significant stretch-induced decrease in SpC in control conditions (31.4±8.6 vs. 23.2±6.4%, p<0.01) was attenuated under 0.1μM carvedilol (0.1μM: 27.6±8.4 vs. 23.5±6.1%, ns) and 0.1μM VK-II-86 (24.7±5.4 vs. 21.2±3.9%, ns), but not under 1μM of both drugs (carvedilol: 41.3±11.3 vs. 30.3±5.7%, p<0.05; VK-II-86: 34.7±7.2 vs. 28.3±3.9%, p<0.01). Nevertheless, during stretch, arrhythmia regularity and organization was greater (higher SpC) under the highest concentration of carvedilol (p<0.01) and VK-II-86 (p<0.05) than in control conditions (control: 23.2±6.4%, carvedilol 1μM: 30.3±5.7%, VK-II-86 1μM: 28.3±3.9%).

Conclusion

Carvedilol and its analogue VK-II-86 abolished the changes in VF activation frequency produced by myocardial stretch at the highest studied concentration, and also attenuated the stretch-induced activation heterogeneity at the lowest concentration. The similarity in the effects of both drugs on the stretch-induced alterations would imply that its protective effect is due to its ability to inhibit store-overload-induced calcium release.

Detection of mental stress due to oral academic examination via ultra-short-term HRV analysis

Mental stress may cause cognitive dysfunctions, cardiovascular disorders and depression. Mental stress detection via short-term Heart Rate Variability (HRV) analysis has been widely explored in the last years, while ultra-short term (less than 5 minutes) HRV has been not. This study aims to detect mental stress using linear and non-linear HRV features extracted from 3 minutes ECG excerpts recorded from 42 university students, during oral examination (stress) and at rest after a vacation. HRV features were then extracted and analyzed according to the literature using validated software tools. Statistical and data mining analysis were then performed on the extracted HRV features. The best performing machine learning method was the C4.5 tree algorithm, which discriminated between stress and rest with sensitivity, specificity and accuracy rate of 78%, 80% and 79% respectively.

Classification in emotional BCI using phase information from the EEG

Synchronization and distributed functional networks have been used with success in different areas of engineering. In this paper we use the synchronization information from electroencephalogram (EEG) channels through the Phase Locking Value (PLV) as a potential classification method for a Brain Computer Interface (BCI); this achieved using emotional schematic faces as stimuli in a motor imagery (MI) task. Based on the variations of the PLV values for each proposed task and for each participant, the principal channel pairs are identified. Selected channel pairs, corresponding with the accomplished task, present PLV patterns similarly to Evoked Potentials (ERS/ERD) which are widely used as classification features for MI based BCI.

Sub-kilohertz linewidth narrowing of a mid-infrared optical parametric oscillator idler frequency by direct cavity stabilization

We stabilize the idler frequency of a singly resonant optical parametric oscillator directly to the resonance of a mid-infrared Fabry-Perot reference cavity. This is accomplished by the Pound-Drever-Hall locking scheme, controlling either the pump laser or the resonant signal frequency. A residual relative frequency noise power spectral density below 10(3)  Hz(2)/Hz is reached on average, with a Gaussian linewidth of 920 Hz over 100 ms, which reveals the potential for reaching spectral purity down to the hertz level by locking the optical parametric oscillator against a mid-infrared cavity with state-of-the-art superior performance.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

Camillo Golgi as clinical pathologist: epicritical reading of Golgi's works on malaria

Camillo Golgi confirmed, in 1885, Marchiafava's and Celli's discoveries about malaria, following a clinical-pathologic research pattern and studying the patient directly. In 1889 he associated the naturalistic-biological point of view and the clinical-pathologic one so that he made possible a differential diagnosis between tertian and quartan fever, independently from the clinical observation; he supplied useful laboratory data for clinical diagnosis and, in doing so, he created the new figure of the clinical pathologist; he distinguished three different kinds of intermittent fevers and, in 1888, he specified the useful time for quinine administration. The article analyzes, also, his methodological and scientific principles.

Hepatic subcellular storage of beta-carotene in rats following diet supplementation

Beta-carotene (BC) storage was measured in liver and its subcellular fractions (plasma membranes, mitochondria, microsomes and nuclei) of rats fed BC added to diet. The BC supplementation dose was about 350 mg/week/rat. After 15 weeks of this supplementation, rats were killed and their livers were immediately excised and processed to obtain total liver tissue and its subcellular fractions. Their BC contents were measured by HPLC as pmols/mg. protein Intact BC was found to be stored in all the above subcellular fractions, thus showing that BC is probably taken up by liver cell lipid moiety. Interestingly, the mean BC concentrations in plasma membranes and mitochondria were significantly higher than that in total liver tissue. Our data confirmed that rodents are a good animal model for the study of BC metabolism and its effects on several pathologies, and cancer prevention and treatment in humans in spite of the fact that rodents are classified as white-fat animals because of their poor BC absorption and storage in fat and blood plasma, whereas humans are classified as yellow-fat organisms because of their opposite behavior in BC uptake and organ distribution.

Light and electron microscopic immunohistochemical localization of protein gene product 9.5 and ubiquitin immunoreactivities in the human epididymis and vas deferens

The distribution of protein gene product 9.5 (PGP) and ubiquitin immunoreactivities in the ductuli efferentes, ductus epididymidis, and ductus deferens of humans was studied by Western blot analyses and light and electron microscopic immunocytochemistry. PGP immunoreactivity was intense in the ductuli efferentes and weak in the ductus epididymidis and ductus deferens, while ubiquitin immunoreactivity was intense in the ductuli efferentes and ductus epididymidis and very weak in the ductus deferens. In the ductuli efferentes epithelium, PGP immunolabeling was observed in the cytoplasm of principal cells, whereas ubiquitin immunoreactivity was found in the nucleus and cytoplasm of principal cells and ciliated cells. In the ductus epididymidis epithelium, only scattered cells (mitochondria-rich cells) showed PGP immunoreaction in their cytoplasm, whereas ubiquitin immunostaining was detected in the nucleus and cytoplasm of most epithelial cells, except for the cauda, where ubiquitin immunolabeling was observed only in the nuclei. The ductus deferens showed no immunostaining for PGP, and only nuclear immunoreactivity to ubiquitin. The ultrastructural localization of PGP immunoreactivity was in the apical cytosol and microvilli. In addition to these locations, ubiquitin immunoreactivity was also found in the nucleus of all cell types and cilia of ciliated cells. Although the distribution of PGP and ubiquitin immunoreactivities in humans differs from that reported in rats, it seems that PGP and ubiquitinated proteins are secreted into the epididymal lumen in both species.

Carotenoids in cancer, mastalgia, and AIDS: prevention and treatment--an overview

In 1980, two carotenoids, beta-carotene (BC) and canthaxanthine (CX) with and without pro-vitamin A activity, respectively, were orally administered to female Swiss albino mice and were found to substantially prevent skin carcinogenesis induced by benzo(a)pyrene (BP). This preventive effect was observed in darkness by means of photocarcinogenic enhancement (PCE) following UV (300 to 400 nm) irradiation. In 1984, the same experiment produced antitumorigenic activity when applied to breast carcinogenesis induced in mice by 8-methoxypsoralen (8-MOP) plus UV-A light and, in 1985, when directed toward gastric carcinogenesis induced in rats by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). These data suggested a rationale for human intervention to prevent, by carotenoid supplementation, a second primary malignancy after the primary malignancy has been radically excised. In the 1980s, a pilot clinical study (15 cases) showed a longer than expected disease-free interval in all surviving patients. It was also subsequently found that, if treated daily with 20 mg of BC and intermittently with retinol 150 to 300,000 IU daily for seven days just prior to menses, women suffering from cyclical mastalgia were relieved from pain, without any toxic side effects. When BC was given in high daily doses (60 mg) to 60 drug addicts suffering from AIDS-related complex (ARC), they recovered from their objective and subjective symptoms (but not from lymphadenopathy) with improvement in their general health and increased performance status. At higher doses, BC (with or without hyperthermia) was effective even in patients in advanced stages of AIDS. A debate has arisen concerning a recent statement by the U.S. Government that "beta-carotene supplements do not protect Americans against cancer or heart disease, and may actually increase the risk of deadly lung tumors in smokers".

Whole body hyperthermia associated with beta-carotene supplementation in patients with AIDS

The objective of this work was to check possible additive beneficial effects of whole body hyperthermia (WBH) associated with beta-carotene (BC) supplementation in patients with AIDS. In a pilot study, 10 HIV positive patients, (8 with AIDS and 2 with AIDS related complex, ARC), after AZT or DDI discontinuation, were first treated with one single session of WBH applied with a non-invasive procedure at 42 degrees C core temperature for one hour, and subsequently supplemented with BC 120 mg daily continuously. All patients well tolerated the non-invasive WBH as well as the high dose BC supplementation. Apart from one patient who died after 4 months, all the others underwent an HIV burden diminution, clinical improvement and amelioration of laboratory data, along with an subjective improvement of their life quality. With reference to control groups, namely (a) only WBH applied with extracorporeal procedure to 31 AIDS patients, and (b) only BC supplementation at high dosage applied to 64 ARC patients, the combined physical and BC supplemental treatments clearly showed a better and longer lasting response.

Giant cell formation in Hodgkin's disease

The identity of Reed-Sternberg cells in Hodgkin's disease has remained an unresolved issue, though many studies have addressed this question. Giant cells are usually formed either by endomitosis without cytoplasmic division or by cell fusion through cytokines or viruses. Growing evidence associates Epstein-Barr virus (EBV) with Hodgkin's disease, a major issue being whether EBV is a passenger virus or has an aetiological role. This communication describes experimental conditions enabling observation of giant cell cytogenesis from peripheral blood mononuclear cells in culture. Mononuclear cells were isolated from autologous peripheral blood and cocultured with a single-cell suspension obtained from Hodgkin's lymph nodes in a culture chamber where the two cell populations are isolated by a microporous membrane that allows only cytokines and viruses to pass through. Under these experimental conditions, giant cells are formed in the peripheral blood mononuclear cell fraction; some of them appear morphologically indistinguishable from Reed-Sternberg cells and their mononuclear variant, while others much resemble Langhans giant cells. Some of these giant cells are positive for EBV DNA by in situ hybridization. These results suggest that an EBV-dependent biological activity is responsible for giant cell cytogenesis originating from lymphocytes and monocytes, induced either by EBV and/or cytokines.

A morphological and functional assessment of Mycobacterium leprae-induced nerve damage in a guinea-pig model of leprous neuritis

Nerve damage, resembling that caused by Mycobacterium leprae in man, was created by the injection of cobalt-irradiated M. leprae organisms into the tibial nerve of guinea-pigs. Assessment of nerve damage was made by clinical, electrophysiological and morphometric means at intervals up to 13 weeks after injection. Quantitative immunohistochemical analysis of neuropeptide-containing fibres in the skin of the foot was also carried out. Significant nerve damage occurred 3 weeks after injection of M. leprae organisms. Motor and sensory functional loss peaked at 5 weeks after injection, and there was a significant decrease of peptide-immunoreactive nerves in all skin compartments. The nerve damage was self-limiting and functional recovery had occurred by 13 weeks. The model shows many of the features found in the nerve damage of treated leprosy patients.

Denatured muscle grafts for nerve repair in an experimental model of nerve damage in leprosy. 2. Recovery of peripheral peptide-containing nerves assessed by quantitative immunohistochemical study

A marked depletion of neuropeptide-immunoreactive nerves, a consequence of the nerve damage which is commonly found in leprosy, has been reported in peripheral tissues of leprosy patients and of a leprosy animal model. The aim of this study was to investigate peripheral reinnervation following a denatured autologous muscle graft in an animal model of leprosy nerve damage. Possible reinnervation of the foot-pad skin was studied by immunohistochemistry using antisera to the neuronal marker protein gene product 9.5 (PGP), the neuropeptides calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP), and the C-flanking peptide of neuropeptide Y (CPON). The extent of the reinnervation process was assessed by image analysis quantification at different time points. At 8 weeks after muscle grafting, there were small numbers of immunoreactive nerves (p < 0.05). At 12, 16, and 20 weeks postoperatively there was a gradual increase in all immunostaining. At 20 weeks, no significant difference was found for PGP-, CGRP-, and SP-immunoreactive nerves in the epidermal and subepidermal layers compared to control (contralateral) tissue. In experimental tissue the recovery of immunoreactive nerves around sweat glands took longer (up to 12 weeks) than in other skin compartments, but after that time the recovery was rapid and at 20 weeks no difference was measured for VIP-immunoreactive nerves in comparison with controls. Around blood vessels, the recovery of CGRP- and CPON-immunoreactive fibers was slow, and at 20 weeks a difference with control samples (p < 0.01) was noted. In the same area, there was no significant difference for PGP immunoreactivity between controls and tissues at 20 weeks. In contrast, the immunoreactive nerve bundles in the dermis showed a faster recovery than nerves in other skin areas, with amounts similar to controls at 20 weeks. The significant recovery of immunoreactive nerves, in particular of those containing sensory neuropeptide, is consistent with the described functional recovery.

Short communication: possible activity of beta-carotene in patients with the AIDS related complex. A pilot study

In a pilot single blind study, beta-carotene (BC) supplementation produced, in ARC patients under current treatment, apparent recovery from asthenia, fever, nocturnal sweating, diarrhoea, loss in weight, and led as a result to an improvement in general health and working efficiency, but not to an improvement in multiple district lympho-adenopathies. Nevertheless, BC appeared to prevent progress to AIDS and, in addition, to lower the effective dosage of AZT used in one case of ARC developed into AIDS, producing a recovery from opportunistic infections and an inhibition of Kaposi sarcoma diffusion, in line with a two-fold rise in CD4 counts.

Carotenoids reduce the chromosomal damage induced by bleomycin in human cultured lymphocytes

The supplementation with beta-carotene and canthaxanthin, two carotenoids with and without pro-vitamin A activity, reduced in vitro the number of micronuclei induced in human cultured lymphocytes by the chemotherapeutic radiomimetic drug bleomycin. The genotoxic activity of this substance is supposed to be mediated by a free radical mechanism. The reduction of micronucleated cells was in correlation with donors' carotenoid blood levels. It has been observed that 20 weeks are needed, following the end of carotenoid supplementation, in order to return to the high levels of micronuclei induced by bleomycin. It is suggested that this protective effect is due to the antioxidant properties of carotenoids acting against free radical-mediated genotoxic damage.

Carotenoids in cancer chemoprevention and therapeutic interventions

Carotenoid (CARs: beta-carotene BC and/or canthaxanthin CX) supplementation have been shown to be chemopreventive in animals, since 1980, against direct or indirect chemical carcinogenesis/photo-carcinogenesis of the skin, breast, stomach, salivary glands, colon-rectum, urinary bladder, and against transplanted tumors. This action could be either independent of or dependent on pro-vitamin A activity of BC. In vitro, both BC and CX proved to be antimutagenic and to have anti-malignant transformation properties in cell cultures. Preliminary interventions in humans with BC +/- CX prevented the onset of second primary tumors in lung, colon, urinary bladder, and head and neck. The powerful antioxidant properties of CARs, possibly associated with their retinoid potential, played a role in all the above observations, producing free-radical quenching and immunostimulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Free radicals as carcinogens and their quenchers as anticarcinogens

An oxygen dependent signal was detected, late in the 1950s by electron spin resonance (ESR) in a saline solution of hematoporphyrin (Hp) excited by light. This signal expressed a free radical consisting of 'some kind of an association between Hp and oxygen', that Smaller et al. called 'oxyradical' (HpOO.). It soon opened a new level of understanding in carcinogenesis triggered by photodynamic substances, including Hp itself, polycyclic hydrocarbons (PCHs), as well as any carcinogen involving molecular species activated by radiation and/or metabolic reaction. Early in the 1960s, this prompted the discovery of benzo(a)pyrene (BP) photocarcinogenic enhancement (BP-PCE) in mice, probably due to an increase in free oxygen radical generation following correct light exposure. This assumption was confirmed in 1980 by the fact that mice orally loaded with antioxidants and radical quenchers, such as beta-carotene (BC) and cantaxanthin (CX), were protected against BP-PCE at 100% and against total BP carcinogenicity at more than 60%. These achievements were presented as the bases of the current explosion of interest in biology and medicine in building up the new field of chemoprevention against cancer and other chronic diseases by supplementation with antioxidant vitamins, retinoids and especially carotenoids and their synergistic association. The relevant findings of this research obtained in the last decade in in vitro and in vivo experiments as well as human interventions are reported and discussed with personal contributions.

Quantitative and ultrastructural alterations in the lamina propria and Sertoli cells in human cryptorchid testes

A quantitative and ultrastructural study was performed on biopsies of human cryptorchid testes to investigate lesions in the lamina propria and Sertoli cells. Prepubertal cryptorchid testes (1-9 years of age) were classified into four groups: Type 1, testes with minimal lesions; Type II, testes with a moderate decrease in tubule diameter and spermatogonal number; Type III, testes with Sertoli cell hypoplasia and a marked reduction in tubule diameter and spermatogonal number; and Type IV, testes with Sertoli cell hyperplasia and a variable reduction in spermatogonal number. An increase in thickness of the lamina propria was found in Type II and III testes from 5 years of age onwards. These testes also showed a decrease in both the average number of peritubular cells per cross-sectioned tubule and in the average nuclear volume of these cells. Most of the postpubertal cryptorchid testes from 13- to 18-year-old youths presented a prepubertal pattern suggestive of delayed testicular maturation. Postpubertal testes from 19- to 27-year-old men were classified into three types: Type A testes showed complete spermatogenesis, mature Sertoli cells and no lesions in the lamina propria; Type B testes showed isolated spermatogonia, mature Sertoli cells, and a marked thickening of the lamina propria; and Type C testes showed isolated spermatogonia, hyperplasia of immature Sertoli cells, and a slightly thickened lamina propria. Maturation of the lamina propria was always associated with maturation of the Sertoli cells. Thickening of the lamina propria was associated with peritubular cell alterations consisting of decreases in the nuclear volume (average and total per testis) of peritubular cells and increases in the number of these cells per cross-sectioned tubule. The three types of adult cryptorchid testes appear to be the postpubertal transformation of Type 1 testes (Type A), Type II and Type III testes (Type B), and Type IV testes (Type C).

Reduction of chromosomal damage by bleomycin in lymphocytes from subjects supplemented with carotenoids. Relevance in bleomycin tumour chemotherapy. Preliminary results

In a one year-study, 9 healthy human donors were being supplemented with beta-carotene (BC) plus canthaxanthin (CX), to determine the effect of carotenoids on chromosomal damage (micronuclei) induced in the donors' lymphocyte cell cultures by exposure to bleomycin (BLM), an antineoplastic drug that has been shown to produce chromosomal aberrations through the production of free radicals. The first four months monitoring data, including determination of carotenoid blood levels, are here reported. These data show that carotenoid supplementation significantly decrease (up to 50%) the formation of micronuclei induced by BLM in human lymphocyte cell cultures. This decrease is in correlation with carotenoid blood levels.

Multinucleate epithelial cells in the ductuli efferentes of human epididymis

The histological and ultrastructural study of the ductuli efferentes in epididymides from 40 adult men revealed the occurrence of multinucleate epithelial cells in all specimens. These cells appeared in the luminal protrusions of epithelial folds and correspond to either principal or ciliated cells. The ultrastructure of their cytoplasm did not differ from that of their respective mononucleate cells. Multinucleate cells contained 3-20 closely juxtaposed nuclei, thus appearing much more irregularly outlined than those of the mononucleate epithelial cells. Multinucleation four times more frequent in the principal cells than in the ciliated cells. The number of multinucleate cells increased progressively from the age of 60 years onwards. The average number of nuclei per cell increased in the fourth decade of life, was maintained up to the eighth decade, and then increased again.

Laminin, type IV collagen, and fibronectin in normal and cryptorchid human testes. An immunohistochemical study

An immunohistochemical study of laminin, type IV collagen, and fibronectin was carried out in the testes of normal men and in the cryptorchid and contralateral scrotal testes of cryptorchid men from 2 to 40 years of age. The integrated optical density (IOD) per unit area of the lamina propria was measured in the immunostained sections. Fibronectin was found throughout the thickness of the lamina propria of the seminiferous tubules and in the interstitial connective tissue. No differences between normal and cryptorchid testes were found. Laminin was observed in the innermost part of the lamina propria of the seminiferous tubules and surrounding the endothelium of blood capillaries from infancy. No differences were found between normal and cryptorchid testes in the prepubertal period. In adult cryptorchid testes, laminin formed more numerous and deeper invaginations towards the seminiferous epithelium than in normal adult testes. Type IV collagen appeared throughout the thickness of the lamina propria of normal testes as well as in the wall of interstitial blood vessels. From infancy, the lamina propria of seminiferous tubules, but not blood vessel walls, showed lesser immunostaining for type IV collagen and a lower IOD of this component than did control tests from men of the same age. No differences between unilateral and bilateral cryptorchidism were found. The contralateral scrotal testes of cryptorchid males showed intermediate immunostaining for type IV collagen between that of normal control testes and that of cryptorchid testes. These findings suggest that the lamina propria of seminiferous tubules is lesioned at an early age in both cryptorchid and contralateral scrotal testes of cryptorchid men.

Photobiological effects in Saccharomyces cerevisiae induced by the monofunctional furocoumarin 4,4',6-trimethylangelicin (TMA) and the bifunctional furocoumarin 8-methoxypsoralen (8-MOP)

Recently, the monofunctional furocoumarin 4,4',6-trimethylangelicin (TMA) has been proposed for photochemotherapeutic use. In order to assess its genotoxic potential, the photobiological (genetic) effects of TMA were studied in a diploid strain of Saccharomyces cerevisiae (D7) and compared to those of the bifunctional furocoumarin 8-methoxypsoralen (8-MOP). At equimolar concentrations, the induction of lethal effects by TMA in the presence of equal 365-nm radiation was higher than that exerted by 8-MOP. TMA was also more active than 8-MOP in inducing nuclear events such as nuclear reverse mutation and mitotic recombination (crossing-overs and gene conversion) per unit dose of 365-nm radiation. At equal survival, however, TMA was less efficient in inducing reverse mutation and crossing-over, showing the same activity as 8-MOP in the induction of gene conversion. TMA was more active than 8-MOP in the induction of cytoplasmic 'petite' mutations per unit dose of 365-nm radiation and per viable cell. The high photobiological activity of this monofunctional furocoumarin is mainly related to its strong DNA photobinding but also to the type of monoaddition induced, to the sequential distribution in DNA and to the generation of active forms of oxygen.

Acquired cystic transformation of the rete testis secondary to renal failure

The histologic study of testicular specimens from 218 consecutive autopsies revealed a cystic transformation of the rete testis in 26 men. Serial sections of the testes, epididymides, and spermatic cords of these men were studied by light microscopy. In 15 cases, the rete testis dilation was caused by obstruction of the epididymis. In five cases, the dilation was due to obstruction of the intratesticular excretory ducts caused by varicocele. In the remaining six men, no evidence of obstructive processes was found. These six patients had been diagnosed with renal failure and underwent hemodialysis. The rete testis in these men showed dilated channels lined by a high columnar or pseudostratified epithelium. They contained spermatozoa, with a proteinaceous material and calcium oxalate crystals. The ductuli efferents showed eosinophilic granules in their epithelial cells and their lumen contained spermatids, spermatozoa, cell remnants, calcium oxalate crystals, and multinucleate giant cells. These rete testis lesions are similar to those previously reported in the kidney of hemodialyzed patients.

Cancer chemoprevention by supplemental carotenoids in animals and humans

Experiments were carried out in mice demonstrating that dietary carotenoids (beta-carotene or canthaxanthin), starting before cancer initiation and continuing throughout the experiment, have a protective effect against indirect skin carcinogenesis induced by benzo[a]pyrene +/- UVA and breast cancer induced by 8-methoxypsoralen + UVA. Experiments in rats demonstrated that carotenoids also prevent the direct gastric carcinogenesis induced by N-methyl-N'-nitro-nitroso-guanidine. Recently, prevention by beta-carotene against colon cancer induced in mice by dimethylhydrazine, another indirect carcinogen, was confirmed by others. The prospects for carotenoid intervention with humans were based on their antitumorigenic effect, which is quite independent of pro-vitamin A activity, their lack of toxicity even after prolonged administration, and their immunostimulating activity. These facts helped to build up a rationale predicting that any epithelial cancer, after radical surgery, can be chemoprevented with supplemental carotenoids. Thus, it is expected that the remaining initiated epithelial tissue will be protected by quenching oxygen radical formation, against the onset of a second primary malignancy. This type of prevention can be envisaged in organs like the lung, urinary bladder, breast, stomach, and colon-rectum. At present, human intervention protocols with a randomized drug/placebo method are underway under the supervision of the Centro Tumori of Pavia to chemoprevent with beta-carotene second primary lung or bladder cancer after radical surgery. Preliminary observations regarding findings in humans without randomization (1980-1988) in Pavia are also reported here. This consisted of chemoprevention with beta-carotene plus canthaxanthin against recurrence of different epithelial malignancies after radical treatment (surgery +/- chemoradiotherapy). None of the 11 cases recruited, on the basis of radical nature of treatment and patient adherence, have shown any recurrence beyond their expected disease-free intervals.

Beta-carotene supplementation associated with intermittent retinol administration in the treatment of premenopausal mastodynia

Twenty-five women, 23-41 year old, suffering from premestrual cyclical mastodynia linked or otherwise to benign breast disease (BBD), with moderate or severe pain at least seven days before each menstrual period, were treated with daily beta-carotene (BC) supplementation associated with intermittent administration of retinol (all-trans-retinol 300,000 IU per day). In this therapy retinol was given for 7 days immediately before each menstrual period. After 6 months' treatment, the results revealed marked reduction in breast pain, and sometime recovery, in 23-41 year old women with no toxic side effects. But no such advantages in 5 women with non-cyclical mastodynia treated as above were found. Above this age range, the advantages appear to be absent. All the women developed a healthy look because of a slight tanning of the skin due to beta-carotene supplementation. These data demonstrated a therapeutic synergism between BC and retinol.

Proliferative activity of human spermatogonia from fetal period to senility measured by cytophotometric DNA quantification

The proliferative activity of human spermatogonia from the fetal period to senility was studied by means of cytophotometric quantification of the nuclear DNA content in histological sections. Proliferating spermatogonia that were replicating or had replicated their DNA (DNA content between 2.5c and 4.5c) were observed in all ages. The percentages of these spermatogonia were high (18.2%) in the second trimester of gestation, decreased in the third trimester (8.2%), maintained similar values in newborns (7.1%) and infants (9.5%), and increased markedly in 4- to 9-year-old children (22.5%). The latter percentage was maintained during puberty (20.1%), decreased significantly in adulthood (17.8%), and was higher in aging testes (25.2%). About 2% of spermatogonia with a DNA content higher than 4.5 c were observed from 4-15 years of age as well as in the testes of elderly men. Sertoli cells replicating their DNA were observed only in fetuses.

Chemoprevention of indirect and direct chemical carcinogenesis by carotenoids as oxygen radical quenchers

Beta-carotene (BC) and canthaxanthine (CX), two carotenoids with and without pro-vitamin A activity, respectively, were found to help to prevent benzo[a]pyrene (BP)-induced skin carcinogenesis in the dark and BP photocarcinogenesis (UV 300-400 nm) when given as an oral supplement to female Swiss albino mice. The same experimental procedure was adapted to 8-methoxypsoralen (8-MOP) photoinduction of mammary carcinomas in mice. Here also, the two carotenoids were strongly antitumorigenic. Indeed, 8-MOP photomutagenesis, tested in S. typhimurium TA 102, appeared to depend on a two-step reaction, namely an oxygen-independent DNA-8-MOP photoadduct, followed by an oxygen-dependent second step, sensitive to carotenoids. This result suggests that dietary carotenoids (powerful antioxidant molecules) might prevent the carcinogenic risk caused by substances that are transformed into ultimate carcinogens by oxidative processes which are indirectly carcinogenic. Finally, to verify whether supplemental carotenoids can affect carcinogenesis where neither light excitation nor oxidative metabolic processes are involved, an experimental attempt was made on gastric carcinogenesis induced in rats by the direct carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The results demonstrate that supplemental carotenoids do not affect initiation and progression stages, but do prevent the progression stage of dysplasias to infiltrating gastric carcinomas. Thus, this provides strong presumptive evidence for oxygen radical involvement in the later stages of this neoplastic development, as recently reported in the literature. As far as mutagenicity in S. typhimurium is concerned, carotenoids do not exert, as expected, any protective effect on MNNG mutagenic activity. The above experimental data suggest that supplemental carotenoids, instead of sunscreen preparations, can be adopted by outdoor workers to prevent skin cancer. Accordingly, such natural antioxidants may be useful in human chemoprevention against neoplasias of the lung, breast, urinary bladder, and colon and rectum even after radical surgery.

Diverticula of human seminiferous tubules in the normal and pathologic testis

The occurrence of diverticula in human seminiferous tubules was investigated in the adult human testis in normal as well as physiologic (aging) and pathologic (germ cell depletion, obstruction of male excretory ducts, varicocele and systemic arteriosclerosis) conditions. Diverticula, which are evaginations of the seminiferous epithelium surrounded by a thin tunica propria, were present in all groups studied. The number of diverticula per mm2 testis was higher in the testis with obstruction than in those without obstruction at each age considered. The number of diverticula increased with age in both the obstructed and nonobstructed testis. No changes in the number of diverticula per mm2 testis were found in relation to systemic arteriosclerosis or different degrees of germ cell depletion. Varicocele was only associated with increased numbers of diverticula when it was also associated with obstruction. The formation of diverticula in human seminiferous tubules seems to be an obstructive process related to increasing age.

Decrease in the number of human Ap and Ad spermatogonia and in the Ap/ Ad ratio with advancing age. New data on the spermatogonial stem cell

The numbers of Ap and Ad spermatogonia per unit section of the testis were calculated in autopsy specimens from young adults and elderly men without testicular pathology. The number of Ap spermatogonia decreased from the 6th decade of life, whereas that of Ad spermatogonia began to decrease in the 8th decade. Although it has been reported that Ad spermatogonia are more sensitive to noxious agents than Ap spermatogonia, the involution of Ap spermatogonia precedes that of Ad spermatogonia. These findings provide new information on concepts relating to the spermatogonia precedes that of Ad spermatogonia. These findings provide new information on concepts relating to the spermatogonial stem cell in man.

Multinucleate Leydig cells in normal human testes

The number of mononucleate and multinucleate Leydig cells per unit area of the testis was determined in normal adult men using the peroxidase-anti-peroxidase method for testosterone detection. The results of this study indicate that the number of multinucleate Leydig cells increases markedly with age, whereas the total Leydig cell population decreases.

Quantitative and ultrastructural study of Leydig cells in Klinefelter's syndrome

This ultrastructural and quantitative study of Leydig cells in Klinefelter's syndrome has been performed using the entire testes obtained from four autopsies plus testicular biopsies from 20 patients. The total Leydig cell volume per testis in Klinefelter's syndrome was similar to that of control testes. However, the total number of Leydig cells per testis was significantly lower in the patients with Klinefelter's syndrome than in the controls. This may be attributed to the Leydig cell hypertrophy that these patients underwent. In patients with Klinefelter's syndrome the average volume of each Leydig cell was significantly higher than that of the controls. Electron microscopic findings revealed that besides ultrastructurally normal Leydig cells there were three other morphologically abnormal Leydig cell types: abnormally differentiated cells; multivacuolated cells; and immature Leydig cells. The ultrastructurally normal Leydig cells were probably the cells principally responsible for testosterone biosynthesis in these patients, whereas the other Leydig cell types were probably barely or not at all functional. The hypertrophy showed by the ultrastructurally normal Leydig cells may be interpreted as an attempt to increase testosterone production.

Obstruction of the tubuli recti and ductuli efferentes by dilated veins in the testes of men with varicocele and its possible role in causing atrophy of the seminiferous tubules

Hormone measurements, spermiograms and testicular biopsies studies were performed in young with varicocele. In addition, the testes and epididymides of 27 adults with varicocele were obtained from autopsies. Light and electron microscopic examination of biopsy and autopsy specimens revealed two types of lesions in testes with varicocele: 1) a diffuse lesion consisting of abnormal spermatozoa and spermatid morphology and sloughing of immature spermatozoa and spermatid; 2) focal lesion, distributed irregularly throughout the testicular parenchyma, affecting several small groups of seminiferous tubules. Each of these groups corresponded to a testicular lobule and showed different degrees of tubular atrophy, so that the focal lesions were distributed in a mosaic pattern. The testicular interstitium showed dilated veins and venules, and progressive collagenization. Some testes showed dilated veins in the rete testis, which compressed several tubuli recti and caused tubular atrophy in the seminiferous tubules opening into these tubuli recti. Other testes showed dilated young veins among the ductuli efferentes, and the rete testis channels appeared to be dilated. Among the different etiological mechanisms which have been suggested to for testicular lesions in varicocele, tubular obstruction at the level of either the tubuli recti or the ductuli efferentes might be responsible for lesions leading to testicular atrophy.

Dietary carotenoids block photocarcinogenic enhancement by benzo (a)pyrene and inhibit its carcinogenesis in the dark

The carotenoids beta-carotene (C) and canthaxanthine (CX), with and without pro-vitamin A activity, respectively, when perorally administered to mice, markedly prevent benzo(a)pyrene photocarcinogenic enhancement (BP-PCE), continue to block such BP-PCE and protect significantly against BP carcinogenesis in mice maintained in the dark. These results appear relevant to both the pathogenesis of chemical carcinogenesis and rational programs of skin cancer prevention in humans.

[Modifications of the enzymatic activity in the calf muscle of the rat in circulatory stasis]

In the attempt to identify enzymatic variations in the sural muscle of rats as a result of arterial ischaemia, the enzymatic variations of LDH, PHI, MDH, GOT, G-6-PDH and CPK were measured in a sural muscle in which both arterial ischaemia and venous stasis were induced. From the results examined it may be concluded that both techniques produce reversible lesions and that there is no significant difference in enzymatic activity between the two experimental conditions.

[Variations in the enzymatic activity in the calf muscle of the rat following ischemia]

Muscle lesions induced by ischaemia have been investigated in depth from the morphological standpoint, though the metabolic changes thus caused are still the subjects of discussion. Measurements were therefore made of enzyme activities in rat calf muscle, and their changes following incomplete ischaemia. Three enzymes were studied: CPK (typical of muscle metabolism), G-6-PDH (pentose cycle, indicator of the extent of repair processes), and uptake of a labelled amino acid (L-leucine, on the part of tissue proteins. An initial increase in activity and uptake was followed by recovery functions, due to installation of a collateral circulation. This appeared to be complete by the 5th day.

Leiomyoma of the female urethra and bladder neck

A case of female urethral leiomyoma is presented. Due to its site of origin, at the bladder neck, the clinical picture resembled that of male prostatic median lobe enlargement. TUR was performed successfully and the authors feel that this should be considered the procedure of choice for leiomyomas arising in the proximal female urethra.